Signal processing apparatus



FIG. 1 is a perspective front view of an embodiment of a signal processing apparatus according to the present invention.

FIG. 2 is a left side elevation view of the signal processing apparatus of FIG. 1.

FIG. 3 is a right side elevation view of the signal processing apparatus of FIG. 1.

FIG. 4 is a rear elevation view of the signal processing apparatus of FIG. 1.

FIG. 5 is a front elevation view of the signal processing apparatus of FIG. 1.

FIG. 6 is a top view of the signal processing apparatus of FIG. 1; and,

FIG. 7 is a bottom view of the signal processing apparatus of FIG. 1. 

CLAIM I claim the ornamental design for a signal processing apparatus, as shown and described. 